Removal Of Heavy Metal Ion From Wast Water By Biosorption Method

Biological absorption is a kind of promising water treatment method in recent years. It has been becoming a hotspot content at home and abroad for its advantages of resourceful raw material, low cost, no second pollution, so it will have development future and application prospect.The adsorption rate of beer yeast to Pb²⁺ is 82.80%. Adsorption of beer yeast immobilized by 2% PVA and 1% SA as embedding agents on Pb²⁺ ions has the optimum effect. The result showed the amount of beer yeast is 20g/L, ratio of the embedding agents is 2∶1, concentration of CaCl₂ is 3%(W/V), the immobilized time is 4h, respectivly. The absorption efficiency of untreated yeast immobilized was 92.65%, when the pH value was 4.0, the Pb²⁺ ion initial concentration was 0.2413 mmol·L^-1, the amount of beer yeast was 20g/L, the temperature was 28℃,shaking absorption time was 3h. Under these conditions, the absrption rate is 91.78% when industrial waste water of Pb²⁺ ions was treated by beer yeast immobilized. By using 1.0 mol·L^-1 HCl as eluent azent, the absorption efficiency was up 70% and the elution efficiency was 90%.The adsorption model of beer yeast immobilized on Pb²⁺ ions was conformed to the Langmuir isothermal adsorption equation and the Freunlich isothermal adsorption equation. The dynamics adsorption model of beer yeast immobilized on heavy metal ion was conformed to pseudo-second-order.